1. Field of the Invention
The invention relates to a sporting and exercising unit comprising a foot receiving member and a spring member attached to and disposed at the bottom of the foot receiving member. More specifically, the invention relates to such a unit which comprises a novel structure for the spring member which is removably attached to the bottom of the foot receiving member
2. Description of Prior Art
Such sporting and exercising devices are known in the prior art as shown, for example, in our U.S. Pat. No. 4,492,374, Lekhtman et al, Jan. 8, 1985. However, the unit as taught in the '374 patent has some shortcomings as follows:
1. As the spring member is permanently attached to the foot receiving member, the entire assembled unit as illustrated in FIG. 1 of the patent must be carried around in its assembled form. This can be inconvenient. PA1 2. The layers 5 and 7 which form the spring member are attached to each other and to a spring rate and weight adjustment mechanism 13 by an arrangement which includes a buckle 33, a bar 35 and a circular rubber member 39. Because of the nature of the attachment assembly, the spring member does not automatically disassemble under conditions of extraordinary force and this could be dangerous. For example, if a user should tread on the edge of a sidewalk, the arrangement would bend under the user so that the user would fall and possibly sustain injuries as well as sprained or broken ankles. PA1 3. Because of the need for metallic members 13, 15 and 17 in the '374 patent, the unit is relatively heavy. PA1 4. The spring rate and weight adjustment mechanism 13 is cumbersome and heavy. PA1 A) a foot receiving member; PA1 B) a plastic spring member detachably attached to and disposed at the bottom of the foot receiving member, said spring member comprising: